Porcelain-faced crown



Nov. 25, 1930. Y s. e. SUPPLEE 1,782,552

PORCELAIN mom; CROWN Filed 001:. 20, 1928 INVENTOR.

A TTORNEYS.

l I Patented Nov. 25, 1 930 .UNITED STATES,

SAMUEL G. SUPPLEE, or wns'r onnnenffnnw JERSEY :eoncnLAIN-rAcED oitown.1; l

Applicati onfiled October 20,1938. Serial IiTo. 313,668.

My invention relates to a porcelain faced crown. h r 7 It is the generalobject of the invention to provide a porcelainfaced crown'which willpossess great strength and rigidity, to the endthat the porcelain facingwill not readily become separated from the crown.

It is a more specific object to provide a porcelain faced crown whichwill have a plu. i0 rality of thicknesses of metal interposed between aprepared tooth and a porcelain faclng. j

i It is another object toprovide a percelain faced crown having asubstantially reinforced edge frame extending about theside and incisaledges of the porcelain facing.

Other objects will be apparent upon a read ing of the specification.

Briefly stated, the invention in its pre a ferred form includes a swagedtwo-piece or cast crown having awall which may be relatively thinextending over the labial side of a prepared tooth. A metal backingplate for a porcelain facing is secured to the labial 2 side of thecrown, preferably by soldering and so that a relatively thickenedmarginal body of solder is formed along the side and incisal edges ofthe labial side of the crown. It is preferred to provide a reinforcingbody of hard metal, such as clasp metal at theincisal edge of the crown.

In the drawings, which show for illustrative purposes only, preferredforms of the invention- V Fig. 1 is a perspective view of a preparedtooth having an improved porcelain faced crown in place; a

Fig. 2 is a central vertical sectional view of the crown shown in Fig.1;

Fig. 3 is a sectional view taken substantially in the plane of line 33of Fig. 2; V

Figs.4=and 5 are central vertical sectional views illustrating steps inthe manufacture of the crown shown'in the previous figures.

r Figs, 6, 7 and 8 are. similarviews showing a slightly modified form ofconstruction.

In said drawings, 1 indicates conventional- 1y a tooth which is to becrowned. The tooth is preferably prepared to receive a gold or othercrown 2, which substantially fits the tooth surface.

prepared toothland abuts against a shoulder 3. The construction of theporcelain faced crown may best bedescribed in connection with thepreferred methods of manufacture;

Int forming the crown mayfirst make a swaged seamless crown or band ofgold or other suitable metal whichmay be cutaway at the frontbr labialside below the upper edge as indicated at 4, in Fig. 4, thus leavin ineffect at the upper front edge aband 14. may then cover the open labialside of the a crown with a thinner facingor front .wall 5 of gold orother metal whichhas previously beenburnishedto the form of the labialside of the prepared tooth. If desired 1 may make a cast crown such asindicatedat 6, in Fig.6, and cut away the labial face asindicated at 7,in Fig. 7 A relatively thin metal labial facing8 corresponding to thefacing 5 may then'be soldered in place on the cast crown or hand. Thereare other methods of forming the prepared crown such asswaging orcasting the same and grinding or other-. wise removing a part of themetal at thelabial side, so as to form a relatively thin metal facing..It may not always be necessary to form the facing very thin, but it ispreferable to have a thin facing in order that it may be made to conformclosely to the prepared Agold or other thin metal backingis thenprepared for the porcelain veneerfacing 10.

The veneer facing lOispreferably ground. out at the rear side to someextent so as to not be forced outwardly by coming in COD-'85 tact withthe central portion of the labial side of the crown. The thin metalbacking 9 is preferably burnished to thefacinglO, andslight lips areprovidedparound the pe ripheral edges of the back'ingplate 9, so as tohold the veneer face 10 in place as is the usua method of holding theveneerfaces.

The porcelain face 10 andits backing plate'9 may be substantially largerthan the crown v vwhichpreferably fits a prepared tooth rather snugly,andthespace between the labial side a of the crown and the backing plate9 maybe filledwith solder 11 or the'like, so as to. form an integralconstruction. If desired, a body ofhard--metal such as clasp metal maybe placed along the incisal edge of the crown and soldered in place inthe finished integral crown construction. After the soldering has beencompleted the porcelain veneer facing 10 is set in place and the edgesof the soft metal backing 9 are burnished over in the usual manner tohold the veneerfacing 10 in place.

It will be seen that by means of the construction shown, the labial sideof the crown is formed of two distinct thicknesses of metal, namely, theface such as 5, the backing plate 9, and in addition the solder'betweenserves to further thicken and strengthen the labial wall of the crown.The relatively thick body of solder which may extend completely aroundthe side and incisal edges of the labial side of the crown furtherstrengthens the structure around the edges and provides an exceedinglyrigid foundation or framework for holding the porcelain facing about itsmarginal edges. The clasp metal incisal edge 12 when provided is alsoadvantageous in strengthening the entire construction and resistingwear. It has been found in practice that there is little likelihood ofthe veneer facings popping out, and this I believe to be due to theextremely rigid construction of the crown as heretofore described.

While the invention has been described in considerable detail, I do notwish to be stritcly limited to the forms shown, nor to the particularmethods herein disclosed, for changes may be made within the scope ofthe invention as defined in the appended claims.

I claim:

1. A tooth crown comprising a metal crown body shaped to substantiallyfit on the rear and side walls of the prepared exposed end of a tooththe side and rear walls of the crown being of substantially the samethickness, a front wall of thinner metal secured at its edges to theedges of the side walls, a porcelain facing, a backing plate secured tothe rear side of said facing, and a layer of solder between therelatively thin front wall of the crown and the rear wall of saidbacking plate.

2. A tooth crown comprising a. metal crown body shaped to fit on therear and side walls of the prepared exposed end of a tooth, the side andread walls being of substantially the same thickness, an integral bandconnecting the sides of the crown body at the top front edges thereof, afront wall secured at its edges to the side walls and the band of saidcrown body, said front wall being of thinner metal than the balance ofthe crown body, a porcelain facing, a backing plate secured to the rearside thereof, and a layer of solder between the relatively thin frontwall of the crown body and the rear wall of said backing plate.

SAML. G. SUPPLEE.

